[woolf7117]

I inherited a pressurized CO2 system that I have been using without problems for more than a month. I came home to find that there is only a tiny trickle of CO2 coming out of my glass diffuser, but nothing like it was yesterday.

There are two gauges on the regulator, one that is a pressure gauge that reads about 70 and the other is the "LPM" gauge which reads 0.

Besides ignorance, what's my problem?

 

[OverStocked]

you're out of co2...

 

[kevmo911]

One gauge is the cylinder pressure gauge. The other is the working pressure gauge. The cylinder pressure gauge will read somewhere around 800psi until the cylinder is almost completely out of CO2, at which point it will start to fall (meaning that when the cylinder is 90% gone it will *still* read 800psi). The working pressure gauge is the one you set (though, in some cheap rigs, it's preset at a certain psi - something like 25 or 30psi).

Generally, 10-20psi is all you need the working pressure to be set at. If you have an atomic diffuser, which won't function below 30+psi, you might want the working pressure to be set at around 40psi.

Anyway, for the vast majority of the life of the CO2 cylinder, one gauge will read 800psi and the other will read 20-40psi (or whatever you set it at). And they won't change until it's time to refill the cylinder.

One other thing - on most gauges, there will be two sets of numbers. One is psi (Pounds per Square Inch), and the other might be kpa or bar. You only need to read psi.

 

[woolf7117]

Thank you both for your replies. Attached are the two gauges. I think that the second one reads the amount of gas and the first one is the pressure gauge. The thing is, the first one almost always read 0.

What am I missing?

 

[kevmo911]

The first one might be busted. I agree that the second is your cylinder pressure gauge, and it shows that you've still got CO2 left.

What you appear to have is an oxygen regulator which has been attached to a CO2 cylinder (I assume you have a CO2 cylinder, anway. The pressure is correct). LPM is Liters Per Minute, which would be the amount of oxygen supplied to a patient.

Eek. Okay, Oxygen cylinders are pressurized to 2000psi. Based on that pressure, as you open a valve little by little, a certain volume of gas is allowed to flow out. That's measured in LPM. I just don't know enough about how an oxygen regulator works to be able to make any assumptions about any sort of working pressure.

In any case, there should be a knob. Even if you don't know what the psi is, you can allow a certain amount of gas through. Turning that knob should increase the reading on the LPM gauge. If it doesn't, something's busted.

 

[woolf7117]

Oxygen.

Thanks again. That's really helpful. I probably need something new, since I've crack the knob all the way open and I still only get a trickle of gas. But at least I know now it's not the gas.

 

[Bettatail]

LPM, liter per minute.
it is a flow gauge, but you can translate the LPM unit into psi for most of the LPM type regulator.
it is about 8-9psi per LPM.

 

[Bettatail]

and it is busted.

Add: this type of regulators, the orifice are fixed diameter and really small. easy to get stuck if any debries get in, and I think that is whathappen, if there is no leak.